Gas on Ethereum is cheap most weeks and suddenly expensive in others. Basalts lets you pay a small premium now, and if next week's gas price ends up high, you get paid back in ETH, automatically. No sign-up, and you keep sending transactions exactly as before.
It works like weather insurance, but for gas. You never change how you send transactions. You just hold a policy, a “Gas Cap”, that pays out when gas gets expensive.
- 01Before the week
Choose your limit
Pick how much gas you expect to use and the weekly average gas price you don't want to pay more than. You pay a small price in ETH. The most the cap can pay is locked in the pool the moment you buy, so the money always exists.
- 02The week
Ethereum keeps the score
You keep sending transactions as usual. Every hour the real gas price is read out of an Ethereum block and recorded on-chain. Only the week's average counts, so one unlucky block can't decide anything.
- 03After the week
Get paid if gas was expensive
If the average ended above your limit, the contract pays you the difference on the gas you covered, in ETH. No claim form, nobody to ask. If gas stayed low, nothing happens.
A cap that pays when the week averages more than 3× normal gas (0.180 gwei), up to 30×. Pick your size and a kind of week.
You'd save 0.637 ETH.
Get a real quote →Every cap has a buyer who wants protection and a pool of ETH holders who provide it, earning the price of the cap for taking that risk. Basalts takes a 15% fee on each cap and 10% of pool profits; 40% of those fees go to BSLT stakers, in ETH.
You pay gas
Apps, wallets that pay gas for users, trading bots, AI agents, rollups
- You do
- Buy a Gas Cap for next week.
- You get
- ETH back when gas is expensive. Predictable costs.
- The risk
- If gas stays low, you've spent the premium.
You hold ETH
Long-term ETH holders, stakers, treasuries
- You do
- Deposit ETH into a weekly pool. It backs the caps people buy.
- You get
- The premiums, paid in ETH, every week.
- The risk
- In an expensive week, the pool pays caps out and you can lose part of your deposit.
You hold BSLT
Anyone who believes in the protocol
- You do
- Stake BSLT, the protocol's token.
- You get
- 40% of all protocol fees, in ETH, plus cheaper caps.
- The risk
- BSLT's price can fall; fees depend on usage.
Not us, not a data provider, not the people on the other side of your cap. Here is why, and you can check a live block yourself.
The number comes from Ethereum
Every hour the gas price is copied out of a real Ethereum block, and the contract checks that block's fingerprint against the one Ethereum stores. There's no data provider to bribe and no admin who can type a number.
The money is already there
When a cap is sold, its full maximum payout is locked in the pool. A pool can never owe more than it holds, so there are no margin calls and no bank-run risk.
Claims can't be frozen
There's an emergency pause, but it can only stop new sales. Paying out claims and withdrawing settled money always works. Settings changes wait 48 hours in public first.
Do I need to change how I send transactions?
No. You keep paying gas normally. A Gas Cap is a separate policy that pays you ETH after the week if gas was expensive.
What exactly is the "gas price" here?
Ethereum's base fee, the part of every transaction's gas price that the network sets automatically and burns. It's the same for everyone in a block, which is what makes it insurable.
What if gas stays low?
Then there is no payout and you've spent the price of the cap. That's the trade every insurance makes: a small known cost instead of a large unknown one.
When can I buy, and when am I paid?
Each week's caps are sold in the 3 days before that week starts. The week is usually settled within an hour of ending (up to about a day if Ethereum skipped some hourly records), and you can claim straight away.
Who takes the other side?
ETH holders who deposit into that week's pool. They earn every premium in calm weeks and pay claims in expensive ones.
What is BSLT for?
BSLT is the protocol's token. Stake it to receive 40% of protocol fees in ETH and cheaper caps. 20% of fees buy BSLT back and burn it. Supply is fixed at 1 billion.
How is this different from ETHGas or blockspace futures?
Products like ETHGas let large buyers reserve a specific block a few minutes ahead, through validators. Basalts does something else: it insures your whole week's gas cost, settles on the public average gas price recorded on-chain, and anyone can buy or provide cover from a wallet, with no intermediary.
Is it audited?
Not yet. The contracts have 74 automated tests and a full end-to-end test, and an independent audit is required before mainnet launch. Use only what you can afford to lose until then.